| /******************************************************************************/ |
| /* */ |
| /* Copyright (c) 2009 FUJITSU LIMITED */ |
| /* */ |
| /* This program is free software; you can redistribute it and/or modify */ |
| /* it under the terms of the GNU General Public License as published by */ |
| /* the Free Software Foundation; either version 2 of the License, or */ |
| /* (at your option) any later version. */ |
| /* */ |
| /* This program is distributed in the hope that it will be useful, */ |
| /* but WITHOUT ANY WARRANTY; without even the implied warranty of */ |
| /* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See */ |
| /* the GNU General Public License for more details. */ |
| /* */ |
| /* You should have received a copy of the GNU General Public License */ |
| /* along with this program; if not, write to the Free Software */ |
| /* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ |
| /* */ |
| /* Author: Shi Weihua <shiwh@cn.fujitsu.com> */ |
| /* */ |
| /******************************************************************************/ |
| |
| #include <sys/types.h> |
| #include <sys/wait.h> |
| #include <err.h> |
| #include <errno.h> |
| #include <signal.h> |
| #include <stdlib.h> |
| #include <unistd.h> |
| #include <stdio.h> |
| |
| #define UNUSED __attribute__ ((unused)) |
| |
| static int test_switch = 0; |
| |
| void sighandler(UNUSED int signo) |
| { |
| test_switch = !test_switch; |
| } |
| |
| int main(void) |
| { |
| sigset_t sigset; |
| struct sigaction sa; |
| pid_t pid; |
| int status; |
| int count = 0; |
| |
| sa.sa_handler = sighandler; |
| if (sigemptyset(&sa.sa_mask) < 0) |
| err(1, "sigemptyset()"); |
| |
| sa.sa_flags = 0; |
| if (sigaction(SIGUSR1, &sa, NULL) < 0) |
| err(1, "sigaction()"); |
| |
| if (sigemptyset(&sigset) < 0) |
| err(1, "sigemptyset()"); |
| |
| /* wait for the signal SIGUSR1 to start testing */ |
| sigsuspend(&sigset); |
| if (errno != EINTR) |
| err(1, "sigsuspend()"); |
| |
| do { |
| count++; |
| pid = fork(); |
| if (pid == -1) |
| err(1, "fork()"); |
| else if (pid == 0) { |
| return 0; |
| } else { |
| wait(&status); |
| } |
| } while (test_switch); |
| |
| return 0; |
| } |